Known animal traps generally include some form of trigger with a mechanical kill mechanism powered by a spring. Traps are used to kill various pests, including (in New Zealand) mice, rats, stoats, possums, hedgehogs, cats, weasels and ferrets. In other countries, other pests are of course present.
Known traps generally include three types of trap. Cage traps capture animals alive and allow non target species to be released. Target species are killed by the trapper, which has the advantage that the animal's fur can be more easily removed while the animal is still warm. Leg hold and snare traps physically hold an animal by securely holding its leg. These traps also capture the animal alive and are much lighter and more compact than cage traps.
The third type of trap is the kill trap, which automatically kills animals rather than capturing them alive. These traps generally kill and retain an animal, and therefore require a user to empty and reset the trap. Some users find emptying a trap disagreeable and in some circumstances it may not be practical or may reduce the efficiency of a pest control programme. For example, stoat traps are widely distributed through New Zealand forests. These traps are emptied periodically—approximately every four weeks. The traps are also re-baited at this time. This requires significant labour, since rangers are required to walk the trap line clearing, re-setting and re-baiting the traps. In addition, if a trap is triggered soon after being checked it will be out of action for most of the four week period.
The Applicant has proposed various improvements to animal kill traps in its PCT applications PCT/NZ2010/000037 and PCT/NZ2011/000178, the entire contents of which are hereby incorporated by reference herein. The Applicant has found that further improvements are possible.
McKee (U.S. Pat. No. 4,567,688) discloses an animal cage trap actuated by a pneumatic mechanism. That mechanism is unlikely to work well as it would require a significant force in order to be actuated and the time between movement of the trigger and actuation of the cage closing mechanism would be relatively long. While this mechanism may be suitable for cage trap applications for relatively large pests, it is not well suited to kill-trap applications or to smaller or more cautious animals.
Reference to any prior art in this specification does not constitute an admission that such prior art forms part of the common general knowledge.
It is an object of the invention to provide an improved trigger arrangement and/or an improved trap, or at least to provide the public with a useful choice.